N-t-alkyl-beta-amino propionic acids



United States Patent O 3,260,745 N-t-ALKYL-BETA-AMINO PROPIONIC ACIDSHarry J. Andress, Jr., Pitman, and Paul Y. C. Gee, Woodbury, Ni,assignors to Socony Mobil Oil Company, Inc., a corporation of New York NDrawing. Original application Apr. 18, 1962, Ser. No. 188,564. Dividedand this application June 25, 1964, Ser. No. 378,035

2 Claims. (Cl. 260-534) This application is a division of our copendingapplication Serial No. 188,564 filed April 18, 1962, now abancloned.

This invention relates to the improvement of nonlubricating petroleumfractions such as distillate fuel oils containing additives adapted toinhibit the appearance of sediment during prolonged storage periods, toprevent screen-clogging, to prevent rusting of ferrous metal surfacesand, additionally to inhibit the fuel oils against objectionableemulsification.

It is well known that fuel oils are prone to form sludge or sedimentduring periods of prolonged storage. This sediment, of course, has anadverse effect on burner operation, because it has a tendency to clogscreens and nozzles. In addition to sediment formed during storage, mostfuel oils contain other impurities, such as rust, dirt, and entrainedwater. The sediment and impurities tend to settle out on equipmentparts, such as nozzles, screens, filters, etc., thereby clogging themand causing the equipment to fail, Still further, petroleum distillatefuel oils have a tendency to form objectionable emulsions.

A factor, incident to the storage and handling of distillate fuels,i.e., gasoline and fuel oils, is the breathing of storage vessels. Thisresults in the accumulation of considerable amounts of Water in thetanks, which presents a problem of rusting in the tanks. Then, when thefuel is removed for transportation, sufficient water may be carriedalong to cause rusting of ferrous metal surfaces in pipelines, tankers,and the like.

Generally, in the case of fuel oils, it has been the practice toovercome the aforedescribed difiiculties with a separate additive foreach purpose, i.e., with a sediment inhibitor, an antiscreen cloggingagent, an antirust agent, and emulsion inhibitor. The use of severaladditives, however, gives rise to problems of additive compatibility,thus restricting the choice of additive combinations. In addition, ofcourse, the use of a plurality of additives unduly increases the cost ofthe fuel.

It has now been found that all of the aforesaid problems, i.e.,sedimentation, screen clogging, rusting, and emulsification can besolved by the use of a single fuel oil addition agent. It has beendiscovered that a distillate fuel oil containing minor amounts ofcertain nitrogencontaining compounds is effectively inhibited,simultaneously, against all of the aforementioned difficulties.

Accordingly, it is a broad object of this invention to provide adistillate fuel oil having improved properties. Another object is toprovide a fuel oil having a single additive adapted to inhibitsedimentation, to prevent screen clogging, to prevent rusting of ferrousmetal surfaces with which it comes in contact, and to inhibitemulsification. A specific object is to provide a distillate fuel thatcontains certain nitrogen-containing compounds that achieve theseresults. Other objects and advantages of this invention will becomeapparent to those skilled in the art from the following detaileddescription.

The present invention provides a distillate fuel containing betweenabout 0.5 pound and about 200 pounds per 1000 barrels of fuel of acompound from the group consisting of:

(a) RNHCH CH COOH 3,260,745 Patented July 12, 1966 "ice and

( CHzOHzCOOH wherein R is an alkyl group containing from about four toabout thirty carbon atoms and having a tertiary carbon atom attached tothe nitrogen atom. Such compounds can be prepared, for example, byreacting one mole of glacial acrylic acid at from about 50 C. to about200 C. with one mole of a primary alkyl amine containing from about fourto about thirty carbon atoms, and having a tertiary carbon atom attachedto the nitrogen atom to form compound (a); and by reacting two moles ofglacial acrylic acid with one mole of such a primary alkyl amine at thestated temperatures to form compound (b).

Amines utilizable for forming the aforesaid products are alkyl amineshaving between about 4 to about 30 carbon atoms per molecule, ormixtures of such amines, in which the amino (NH group is attached to atertiary carbon atom. These amines all contain the terminal p.

Non-limiting examples of such amine reactants are tbutyl primary amine,t-octyl primary amine, t-decyl primary amine, t-dodecyl primary amine,t-tetradecyl primary amine, t-octadecyl primary amine, t-eicosyl primaryamine, t-docosyl primary amine, t-tetracosyl primary amine, andt-triacontyl primary amine. The amine reactants can be prepared inseveral ways well known to those skilled in the art. Specific methods ofpreparing the t-alkyl primary amines are disclosed in the Journal ofOrganic Chemistry, vol. 20, page 295 et seq. (1955). Mixtures of suchamines can be made from a polyolefin fraction (e.g., polypropylene andpolybutylene cuts) by first hydrating with sulfuric acid and water tothe corresponding alcohol, converting the alcohol to alkyl chloride withdry hydrogen chloride, and finally condensing the chloride with ammonia,under pressure, to produce a t-alkyl primary amine mixture.

The distillate fuels that are improved in accordance with the presentinvention are distillate fuel oils that are hydrocarbon fractions havingan initial boiling point of at least about F. and an end boiling pointno higher than about 750 F., and boiling substantially continuouslythroughout their distillation range. Such fuel oils are generally knownas distillate fuel oils. It is to be understood, however, that this termis not restricted to straightrun distillate fractions. The distillatefuel oils can be straight-run distillate fuel oils, catalytically orthermally cracked (including hydr-ocracked) distillate fuel oils, ormixtures of straight-run distillate fuel oils, naphthas and the like,with cracked distillate stocks. Moreover, such fuel oils can be treatedin accordance with well known commercial methods, such as, acid orcaustic treatment, hydrogenation, solvent refining, clay treatment, etc.

The distillate fuel oils are characterized by their relatively lowviscosities, pour points, and the like. The principal property whichcharacterizes the contemplated hydrocarbons, however, is thedistillation range. As mentioned hereinbefore, this range will liebetween about 100 F. and about 750 F. Obviously, the distillation rangeof each individual fuel oil will cover a narrower boiling range falling,nevertheless, within the above-specified limits. Likewise, each fuel oilwith boil substantially continuously throughout its distillation range.

Particularly contemplated among the fuel oils are Nos. 1, 2, and 3 fueloils used in heating and as diesel fuel oils, and the jet combustionfuels. The domestic fuel oils generally conform to the specificationsset forth in ASTM Specifications D39648T. Specifications for dieselfuels are defined in ASTM Specifications D97548T. Typical jet fuels aredefined in Military Specification MIL-F- 5624B.

The amount of the additive embodied for use herein that is added to thedistillate fuel depend, of course, upon the intended purpose and theparticular additive selected, as they are not equivalent in theiractivity. Some may have to be used in greater concentrations than othersto be effective. In most cases, in which it is desired to obtain all ofthe aforesaid beneficial results in fuel oil, namely, to inhibitsedimentation, to reduce screen clogging, to prevent rusting of ferrousmetal surfaces, and to inhibit emulsification, additive concentrationsvarying between pounds per thousand barrels of oil and about 200 poundsper thousand barrels of oil will be employed. It may not always bedesired, however, to accomplish all of the aforementioned results. Insuch cases, where it is desired to effect only one or two of suchresults lower concentrations can be used. Thus, if it is desired only toprevent rust under dynamic conditions, as in a pipeline, it has beenfound that concentrations as low as about 2.5 p.p.m., i.e., about 0.5pound of additive per thousaand barrels of oil, are effective, Ingeneral, therefore, the amount of the additive that can be added to thedistillate fuel, in order to achive a beneficial result, will varygenerally between about 0.5 pound per thousand barrels of oil and about200 pounds per thousand barrels of oil. Preferably, it will vary betweenabout 10 and about 200 pounds per thousand barrels of oil.

If it is desired, the distillate fuel compositions can contain otheradditives for the purpose of achieving other results. Thus, for example,there can be present foam inhibitors, ignition and burning qualityimprovers, and others. Examples of such additives are silicones, dinitropropane, amyl nitrate, metal sulfonates, and the like.

The following specific examples are for the purpose of illustrating thedistillate fuel compositions of this invention, and of exemplifying thespecific nature thereof. Included in such examples is the preparation ofcompounds embodied for use in practice of this invention, their use infuel oils, and, for the purpose of comparison, the use of similarproducts but devoid of a tertiary-carbon atom group as aforediscussed.At is evident from the data set forth hereinafter, the products embodiedfor use herein markedly inhibit emulsification whereas similarcondensation products devoid of the t-alkyl group provide fuel oils thatemulsify severely. It is to be strictly understood, however, that thisinvention is not to be limted by the particular additives and fuels, orto the operations and manipulations described therein.

The amine reactants used in the following examples for reaction acrylicacid were as follows: Amine A is a mixture of primary amines having acarbon atom of a tertiary butyl group attached to the amino (-NH groupand containing principally 18 to 24 carbon atoms, and marketed by Rohm &Haas Co. as Primene JMT; and Amine B is commercial oleyl amine.

EXAMPLE 1 A mixture of 303 grams (one mole) of Amine A and 72 grams (onemole) of glacial acrylic acid were stirred at 105 C. for about 2 hoursand at 175 C. for about one hour to produce the N-tertiary .alkylbeta-amino propionic acid; i.e., the compound of Formula a.

EXAMPLE 2.

A mixture of 144 grams (two moles) of glacial acrylic acid and 303 grams(one mole) of Amine A, was stirred at 135 C. for about two hours and at185 C. for one hour to produce the N-t-alkyl beta-amino dipropionicacid; i.e., the compound of Formula b.

4 EXAMPLE 3 A mixture of 72 grams (one mole) of glacial acrylic acid and300 grams (1.0 mole) of oleylamine was stirred at 110 C. for about 4hours to produce N-oleyl beta amine p-ropionic acid.

Sedimentation The test used to determine the sedimentation characteristic of fuel oils is the 110 F. Storage Test. In this test, aSOC-milliliter sample of the fuel oil under test is placed in aconvected oven maintained at 110 F. for a period of 12 weeks. Then, thesample is removed from the oven and cooled. The cooled sample isfiltered through a tared asbestos filter (Gooch crucible) to removeinsoluble matter. The Weight of such matter in milligrams is reported asthe amount of sediment. A sample of the blank, unihibited oil is runalong with a fuel oil blend under test. The effectiveness of a fuel oilcontaining an inhibitor is determined by comparing the weight ofsediment formed in the inhibited oil with that formed in the uninhibitedoil.

EXAMPLE 4 TABLE I Conan. of Sediment, Additive Additive, mg./literlbs/1,000 bbls.

Base Fuel None None 13 Do Example 1 10 4 Example 2 10 9 Screen cloggingThe anti-screen clogging characteristics of a fuel oil were determinedas follows: The test is conducted using a Sundstrand V3 or S1 home fueloil burner pump with a self-contained -mesh Monel metal screen. About0.05 percent, by weight, of naturally-formed fuel oil sediment, composedof fuel oil, water, dirt, rust, and organic sludge is mixed with 10liters of the fuel oil. This mixture is circulated by the pump throughthe screen for 6 hours. Then, the sludge deposit on the screen is Washedoff with normal pentane and filtered through a tared Gooch crucible.After drying, the material in Gooch crucible is washed with a 50-50(volume) acetone-methanol mixture. The total organic sediment isobtained by evaporating the pentane and the acetone-methanol filtrates.Drying and weighing the Gooch crucible yields the amount of inorganicsediment. The sum of the organic and inorganic deposits on the screencan be reported in milligrams recovered or converted into percent screenclogging.

EXAMPLE 5 Using the test fuel oil described in Example 4, blends of theadditives of Examples 1 and 2 in this fuel were prepared. Each blend wassubjected to the Screen Clogging Test, as aforedescribed. Test resultsare set forth in Table II.

TABLE Ill-SCREEN CLO GGING Rust Test in fuel oil The rustingcharacteristics of fuel oils were determined in the Static Rust Test,which simulates conditions encountered in storage vessels, such as, thehome fuel storage tank. In this test, a strip of 16-20 gauge sandblasted steel plate is placed in a clear quart bottle. The length of thestrip is sufficient to reach from the bottom of the bottle into the neckof the bottle without interfering with the cap. One hundred cc. ofsynthetic sea water with pH adjusted to 5 (ASTM D-655) and 750 cc. oftest oil are placed in the bottle. The bottle is capped tightly, shakenvigorously for one minute, and permitted to stand quietly at 80 F. for21 days. At the end of that time the amount of rust that occurs on thesurface of the plate immersed in the water is used as a measure of theeffectiveness of the fuel to inhibit rusting in storage vessels. It isgenerally preferred that no more than 5 percent of the surface should berusted. This test is much more severe than the ASTM Rust Test. Manycompositions that pass the ASTM test fail in the Static Test.

pared. Each blend was subjected to the Static Rust Test. Pertinent dataare set forth in Table III.

TABLE III.STATIC RUST TEST Inhibitor, Example No. Cone, lbs/1,000 bbls.Rusting, percent l 100 50 0 50 Trace 1 Heavy rust.

In reference to inhibiting emulsification, it has been found thatproducts similar to those embodied for use herein but which do notcontain a tertiary carbon atom group as aforedescribed do not inhibitemulsification whereas the products from the defined t-carbon atomcontaining products (Examples 1 and 2) markedly inhibit emulsification.To illustrate such a function performed by the additives useful forpractice of this invention, the products of Examples 1 to 2 wereindividually blended with a distillate fuel oil in concentrations of 25,50, and 100 lbs/thousands barrels of the fuel oil and subjected to thefollowing emulsion test, said fuel oil comprising 60% catalyticallycracked components and 40% straight run components and boiling in therange of 320-640 F.

Emulsion test The procedure for the fuel oil emulsion test is asfollows: a 200 milliliter portion of the fuel to be tested and 20milliliters of distilled water are placed in a clear glass pint bottle.The bottle is tightly capped and set in an Everbach mechanical shaker ina horizontal position such that the maximum degree of agitation isafforded. The shaker is run at its maximum setting for 5 minutes. Thebottle is then removed, and allowed to stand in an upright position inthe dark for 24 hours. At the end of the 24 hour settling period, theappearance of the water layer is noted. The fuel layer is siphoned off,care being taken not to disturb the oil-water interface, and isdiscarded. A fresh portion of the fuel oil being tested is then added.The described sequence of steps is repeated. If no emulsion appears inthe water layer after this sequence has been performed ten times, theoil is considered to have passed the test. On the other hand, if, afterany 24 hour settling period in the procedure, there is any degree ofemulsification in the water layer, the fuel is considered to have failedthe test. This test procedure has been found to provide emulsions ininhibited oils similar to emulsions which occur in these same oils onlyafter prolonged periods of normal handling and storage in the field on acommercial basis.

RATING SCALE FOR REPORTING EMULSION TEST RESULTS Description of EmulsionClean break on the interface of oil and water. No dirt, skin,

or bubbles present.

Very slight skin at the oil-water interface that usually does not breakon tilting the bottle.

Skin at oil'water interface, heavier than #1 and usually accompaniedwith dirt and bubbles on the skin. No evidence of any white emulsion.

First sign of white emulsion. Usually forms at the bottom and in thecenter of the bottle. It is circular in shape and approximately 34 to 1inch in diameter.

Approximately the same amount of emulsion on the bottom of the bottle as#3. However, emulsion is also beginning to form at oil-water interfaceand extends 142 to Me downward into the water layer. Roughly 15% ofwater layer occupied by emulsion.

Circular emulsion at bottom of bottle extends outward and upwardresemblin spokes. Emulsion at the interface a little thicker than Moreemulsion than #5. Thin film of emulsion forming on sides of bottlesurrounding the water layer. Water is still visible looking through thesides and looking up from the bottom of the bottle.

Emulsion on bottom of water layer is almost solid. Emulsion on sides ofbottle is broken in a few spots enabling the operator to see the waterlayer.

Semi-solid emulsion with perforations or bubbles similar to a honeycomb.No water visible except that seen in the bubbles.

Same (inalllSiOll as #8 but with less bubbles. 7590% emulsion Almostcompletely solid emulsion with only a few air bubbles VlSl e. Completelysolid emulsion (mayonnaise type).

The results obtained from the foregoing emulsion test were as follows:

Cone. of Additive lbs/1,000 bbls. Rating Base Fuel plus Example 1 DoBasalt) Fuel plus Example O Base Fuel plus Example It is apparent fromthe foregoing that the additives (Examples 1 and 2) embodied for useherein are markedly effective as emulsion inhibitors whereascorresponding additives (Example 3) but devoid of a t-carbon atom asaforediscussed resulted in severe emulsification.

Although the present invention has been described with preferredembodiments, it is to be understood that modifications and variationsmay be resorted to, without departing from the spirit and scope of thisinvention, as those skilled in the art will readily understand. Suchvariations and modifications are considered to be within the purview andscope of the appended claims.

What is claimed is:

1. As a new chemical compound, adapted for use as addition agents fordistillate fuel oils, a compound from the group consisting of:

(a) RNHCH CH COOH and C HzC HzC O O H C H20 H20 0 O H wherein R is analkyl group containing from about 4 to about 30 carbon atoms and havinga tertiary carbon atom attached to the nitrogen atom.

2. A compound, as defined in claim 1, wherein R contains from about 18to about 24 carbon atoms.

References Cited by the Examiner UNITED STATES PATENTS 2,787,640 4/ 1957Strong 260-534 2,851,345 9/1958 Marsh 44-71 3,054,750 9/1962 Jolly 44-71X LORRAINE A. WEINBERGER, Primary Examiner.

D. P. CLARKE, T. L. GALLOWAY,

Assistant Examiners.

1. AS A NEW CHEMICAL COMPOUND, ADAPTED FOR USE AS ADDITION AGENTS FORDISTILLATE FUEL OILS, A COMPOUND FROM THE GROUP CONSISTING OF-